The Bad Moms star and her husband, Ashton Kutcher, are already parents to 2-year-old daughter Wyatt.
"We're having a boy!" Kutcher announced during an October appearance on Late Night With Seth Meyers. "I was hoping for a girl because first of all, our first girl is unbelievable. But also I figured if we had a girl second, [Mila] might give me one more shot at having a boy and now I don't know. It's even money, she might cut me off. I want, like, 12 of them."